A shire is a traditional term for a division of land, found in the United Kingdom and Australia. In some rural parts of Australia, a shire is a local government area; however, it is not synonymous with "county", which is, in Australia, a lands administrative division. Individually, or as a suffix in Scotland and in the far northeast of England, the word is pronounced /ˈʃaɪər/. As a suffix in an English or Welsh place name, it is in most regions pronounced /ʃɜr/, or sometimes /ʃɪər/. (In south-east England the /r/ is dropped in accordance with normal regional phonology, so that (for instance) "Berkshire" becomes /ˈbɑːkʃə/.)

In Britain, "shire" is the original term for what is usually known now as a county; the word county having been introduced at the Norman Conquest of England. The two are synonymous. Although in modern British usage counties are referred to as "shires" mainly in poetic contexts, terms such as Shire Hall remain common. Shire also remains a common part of many county names.

The word derives from the Old Englishscir, itself a derivative of the Proto-Germanic skizo (cf. Old High German scira), meaning care or official charge.[1] The system was first used in Wessex from the beginning of Anglo-Saxon settlement, and spread to most of the rest of England in the tenth century, along with West Saxon political control. In Domesday (1086) the city of York was divided into shires.[2] The first shires of Scotland were created in English-settled areas such as Lothian and the Borders, in the ninth century. King David I more consistently created shires and appointed sheriffs across lowland shores of Scotland.

The shire in early days was governed by an Ealdorman and in the later Anglo-Saxon period by royal official known as a "shire reeve" or sheriff. The shires were divided into hundreds or wapentakes, although other less common sub-divisions existed. An alternative name for a shire was a "sheriffdom" until sheriff court reforms separated the two concepts. In Scotland the word "county" was not adopted for the shires. Although "county" appears in some texts, "shire" was the normal name until counties for statutory purposes were created in the nineteenth century.

"Shire" also refers, in a narrower sense, to ancient counties with names that ended in "shire". These counties are typically (though not always) named after their county town.

The suffix -shire is attached to most of the names of English, Scottish and Welsh counties. It tends not to be found in the names of shires that were pre-existing divisions. Essex, Kent, and Sussex, for example, have never borne a -shire, as each represents a former Anglo-Saxon kingdom. Similarly Cornwall was a British kingdom before it became an English county. The term 'shire' is not used in the names of the six traditional counties of Northern Ireland.

The county of Devon is also known as Devonshire, although this is not an official name and is not often used outside the county. The counties of Dorset, Rutland and Somerset were occasionally Dorsetshire, Rutlandshire and Somersetshire, but these usages are now considered archaic.

Hexhamshire was a county in the north-east of England from the early 12th century until 1572, when it was incorporated into Northumberland.

In Scotland, barely affected by the Norman conquest of England, the word "shire" prevailed over "county" until the 19th century. Earliest sources have the same usage of the "-shire" suffix as in England (though in Scots this was oftenmost "schyr"). Later the "Shire" appears as a separate word.

Sutherland is occasionally still referred to as Sutherlandshire. Similarly, Argyllshire, Buteshire, Caithness-shire and Fifeshire are sometimes found. Also, Morayshire was previously called Elginshire. There is currently much debate about whether Argyllshire was ever really used.

In Wales, the counties of Merioneth and Glamorgan are occasionally referred to with the "shire" suffix. The only traditional Welsh county that never takes "shire" is Anglesey—in English: in Welsh it is referred to as 'Sir Fon'.

Three LGAs in outer metropolitan Sydney and four in outer metropolitan Melbourne have populations exceeding that of towns or municipalities, but retain significant bushlands and/or semi-rural areas, and most have continued to use "Shire" in the their titles—possibly due to community demand or popularity; or for financial and socio-political gain—whilst others have dropped "Shire" from their titles. These "city-shires" are:

As of 2013 six of the original eight Shires of Virginia are considered to be still extant whilst two have consolidated with a neighbouring city. Most of their boundaries have changed in the intervening centuries.